Lever closure for split ring assembly

ABSTRACT

An apparatus for securing a closure ring to a container wherein the ring is split and has a lever pivotally attached to a plate secured to the ring at one end and a pivot arm attached to a plate at the other end with the attachment plates having identical attachment points such that tooling and welding of the attachment plates is facilitated. The lever latch closure is further improved by forming locking tab on the lever attachment plate proximal the attachment points and extending upwardly through the lever in a closed position.

BACKGROUND OF THE INVENTION

The present invention relates to metal, fiber, plastic shipping and storage drums and containers and other applications such as transformer cases, etc. in which split closing rings of various diameters are utilized to secure a lids or covers. It is more specifically concerned with improvements in the lever closing device of the split ring.

Lever closing devices are commonly used to reduce the effective diameter of a closing ring about a cylindrical container and through compression secure a cover or other related assembly on open head drums or other containers and similar enclosures. In some applications, such as shipping containers, the force resulting from actuating the closing device lever is used in conjunction with a gasket placed between the cover and container to seal the interface encircled by the closing ring. Typically the lever is secured in the closed position by a secure clip which may be separate or attached to either the closing device or closing ring. This secure clip holds the closing device lever in the closed position by affixing the lever to the closing ring or lever attachment arm of the closing device.

Generally lever closing devices are attached to the ends of the split closing ring via a series of resistance welds or rivets on the lever and pivot attachment arms. Commonly, three attachment points are used on the lever attachment arm, including the secure clip for riveted devices, while two are used on the pivot attachment arm. All resistance welds are typically made simultaneously while rivets are installed two at a time or individually.

In the prior art riveted lever closing device two rivets each are used to attach the lever and pivot attachment arms to the closing ring. An additional rivet is used to attach the secure clip to the closing ring. The spacing of the secure clip rivet point relative to those of the lever and pivot attachment arms requires excessive movement during riveting. Different rivet depth settings for the rivets used to attach the lever and pivot attachment arms and that used to attach the secure clip are also required. Further, the odd number of rivets (5) requires that the rivets either be installed in five individual operations using a single rivet machine or in three operations using a double rivet machine in conjunction with a single.

In a welding process, the number and asymmetric nature of the weld points on the lever and pivot attachment arms also complicate the welding process by causing an unequal welding-current distribution between the welding points. Relatively small variations in closing ring diameter make adjustment of the welding process problematic.

The secure clip is generally inserted through slots in the sides of the closing device lever and a loop located on the lever attachment arm to hold the lever in the closed position. The lever is weakened by and sometimes fails (bends) at these slots due to the compressive forces of closing. Each of the forgoing deficiencies highlights the need for an improved ring closure mechanism.

SUMMARY OF THE PRESENT INVENTION

It is the object the present invention to improve the usefulness and reliability of the lever closing device by simplifying the attachment of the closing device to the closing ring and reducing the failure rate of the closing device lever during operation.

A further object of the invention is to reduce the overall cost of the lever device and its attachment to the closing ring.

Each of the foregoing objects and other advantages are accomplished in the invention through an improved lever attachment arm which utilizes closely spaced, symmetric attachment points and eliminates the requirement for slots through the sides of the closing device lever. In the case of riveting, the design of the lever-attachment arm minimizes rivet depth settings and operator movement by eliminating the requirement for a rivet affixing the secure clip to the closing ring. In the case of welding, symmetric closely spaced weld projections result in a more equal distribution of welding currents with less welding power input. The weld projection spacing utilized on the improved lever attachment arm has the additional advantage of simplifying the tooling required to weld the lever-closing device to the closing ring. The invention has the additional benefit of reducing the material content and forming steps required for the Secure Clip.

These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

An improved lever closure embodying the features of the present invention is depicted in the accompanying drawings which form a portion of this disclosure and wherein:

FIG. 1 is a view of a prior art welded lever closing device in the closed position.

FIG. 2 is a view of a prior art riveted lever closing device in the open position. Note the spacing between the secure clip and lever attachment arm rivets.

FIG. 3 is a view of the improved welded lever closing device in the open position

FIG. 4 is a view of the improved welded lever closing device in the closed position with the integral secure clip engaged.

FIG. 5 is a plan view of the closed latch; and

FIG. 6 is a side elevation of a second embodiment, with the secure clip engaged with the pivot arm.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings for a clearer understanding of the prior art and the invention it may be seen from FIG. 1 that a prior art lever closing device 11 includes a lever attachment arm 12 which is attached to one end 13 of a split ring 14. Lever attachment arm anchors lever 16 which is pivotally attached thereto. Pivot attachment arm 17 is attached to the opposing end 18 of split ring 14 and has one end of a pivot arm 19 pivotally connected thereto. The other end of pivot arm 19 is connected to lever 16 such that movement of lever 16 about its connection to lever attachment arm 12 moves the ends 13 and 18 relative to each other. A secure clip 21 is pivotally attached to lever 16. This prior art embodiment has slots 22 in the sides of lever 16 and a loop 23 in lever attachment arm 12 through which secure clip 21 passes when lever 16 is in the closed position. Note that the lever attachment arm is considerably longer than the pivot attachment arm to accommodate the secure clip loop. When the lever closing device is attached to closing ring 13 the length of lever attachment arm 12 dictates the number and spacing of the attachment points 24.

FIG. 2 depicts another prior art lever closing device, in the open and closed positions respectively. Note the distance between the secure clip 21′ attachment point 26 and the attachment points 27 securing lever attachment arm 12′. When the lever closing device is attached to closing ring 13 the distance between attachment points dictates the complexity of the process used to attach the device to closing ring 13 when attached by rivets or welds. It will be understood by those familiar with the art that variations of these lever closing devices, with and without attached secure clip, are used in different sizes and styles to accommodate various containers and other applications.

The lever closing device, depicted in FIG. 3 to 5, is an embodiment of an improved lever attachment arm 31, improved secure clip 32 and improved lever 33 in combination with the other components of the assembly. Improved lever attachment arm 31 carries an upright tab 34 which extends above the height of lever 33 in the closed configuration. Tab 34 has a slot 36 formed therein, also at a height above the height of lever 33 in the closed position. Lever 33 has a longitudinal slot 37 formed in it such that tab 34 extends through longitudinal slot 37 when lever 33 is in the closed position. Secure clip 32 is pivotally attached to lever 33 such that it is selectively engaged in slot 36 when lever 33 is in the closed position. This embodiment is configured to allow engagement of improved secure clip 32 at a point closer to the juncture of closing ring 13 than previous designs. Thus the improved design allows the use of symmetric attachment points 39 to affix the pivot and lever attachment arms to the closing ring while reducing the number of attachment points. The use of symmetric attachment points greatly simplifies the production process and reduces the number of jigs or fixtures necessary to actually construct the lever assembly. It will be understood by those familiar with the art that these attachment points may involve various types of joining or bonding including adhesives, welding and riveting. Significantly, this embodiment moves the engagement of secure clip 32 and lever 33 to a position intermediate the pivot points at each end of pivot arm 41 thereby allowing slot 37 to positioned in the upper surface of lever 31 at al location that is less susceptible to bending moments than the side mounted slots of the prior art.

In an alternate embodiment of the present invention it has been found possible to mount secure clip 32 to the pivot arm 41 and form lateral slots 42 in the pivot arm such that the pivot arm would be latched to tab 34 in the closed position. In this embodiment The secure clip would then engage the pivot arm slot or slots 42 and slot 36 to secure the lever in the closed position. This embodiment can be seen in FIG. 6. Alternatively the secure clip can be used in a similar manner to lock the lever closing device in an open position.

It is to be understood that the forms of the invention shown is a preferred embodiment thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims. 

1. An improvement for closing a sealing ring about a cylindrical container wherein said sealing ring has a first and second ends which abut for a circle, the improvement comprising a. a lever attachment arm affixed to said first end of said ring at two spaced attachment points, b. a lever pivotally mounted to said lever attachment arm at a first pivot, c. a pivot attachment arm affixed to said second end of said ring at two attachment points spaced equidistant with said lever attachment arm attachment points; and, d. a pivot link pivotally mounted at one end to said pivot attachment arm and pivotally attached to said lever at a second end, such that selective movement of said lever about said first pivot moves said first and second ends relative to each other.
 2. The improvement as claimed in claim 1 wherein said attachment points on said pivot attachment arm and said lever attachment arm are weld points and wherein said weld points are spaced apart for equalized welding current.
 3. The improvement as claimed in claim 1 wherein said attachment points comprise rivet attachment points.
 4. The improvement as claimed in claim 1 further comprising a vertical tab formed on said lever attachment arm and extending upward there from, a slot formed in said lever through which said tab extends when said lever is in close conforming relation to said ring, an aperture in said tab distal said ring, and a securing member selectively positioned within said aperture when said lever is in said close conforming relation to prevent displacement of said lever.
 5. The improvement as claimed in claim 4 where in said securing member is pivotally mounted to said lever.
 6. The improvement as claimed in claim 4 wherein said securing member is pivotally mounted to said pivot link.
 7. In a closure system comprising a split ring, a lever attached to a first arm affixed to one end of said ring and to a pivot link pivotally connected to a second arm affixed to a second end of said ring, the improvement comprising symmetric attachment points formed on each leg for attachment of said legs to said ring.
 8. The improvement as claimed in claim 7 wherein said attachment points on said pivot attachment arm and said lever attachment arm are weld points and wherein said weld points are spaced apart for equalized welding current.
 9. The improvement as claimed in claim 7 wherein said attachment points comprise rivet attachment points.
 10. The improvement as claimed in claim 7 further comprising a vertical tab formed on said lever attachment arm and extending upward there from, a slot formed in said lever through which said tab extends when said lever is in close conforming relation to said ring, an aperture in said tab distal said ring, and a securing member selectively positioned within said aperture when said lever is in said close conforming relation to prevent displacement of said lever.
 11. The improvement as claimed in claim 10 where in said securing member is pivotally mounted to said lever.
 12. The improvement as claimed in claim 10 wherein said securing member is pivotally mounted to said pivot link. 